Hurricane Irma hit Florida as a Category 4 storm the morning of Sept. 10, 2018, ripping off roofs, flooding coastal cities, and knocking out power to more than 6.8 million people. By Sept. 11, Irma weakened significantly to a tropical storm as it powered north toward Georgia and Alabama. At 11 p.m. later that day, it weakened further to a tropical depression, and by Sept. 13, it had dissipated over western Tennessee.
The storm and its aftermath has killed at least 38 in the Caribbean, 34 in Florida, three in Georgia, four in South Carolina, and one in North Carolina. Irma is the fifth-costliest hurricane to hit the mainland United States, causing an estimated $50 billion in damage, according to the National Hurricane Center.
FAQs: What you need to know about Hurricane Irma, and learn how you can help
- How did Hurricane Irma develop?
- When is hurricane season?
- What’s the difference between a tropical depression, tropical storm, hurricane, and major hurricane?
- What is a hurricane category, and what do they mean?
- Why is Hurricane Irma a big deal?
- Where did Hurricane Irma hit?
- When did Hurricane Irma hit Florida?
- How much damage did Hurricane Irma cause?
- How has World Vision responded?
- How can I help Hurricane Irma survivors?
How did Hurricane Irma develop?
Hurricane Irma began Aug. 30 near the Cape Verde Islands. It was the ninth named storm and fourth hurricane of the 2017 storm season.
Irma developed from a tropical wave that developed off the West African coast two days earlier. It rapidly strengthened into a Category 2 storm within 24 hours. Irma’s intensity fluctuated in the days to follow and on Sept. 4 became a Category 4 hurricane.
A day later on Sept. 5, it grew to Category 5 strength. Irma wrought catastrophe in Barbuda and parts of the U.S. and British Virgin Islands. Puerto Rico, the Dominican Republic, and Haiti each experienced flooding and heavy damage in some areas, but the storm left much less destruction than expected.
Hurricane Irma downgraded to a Category 4 Sept. 8, but maintained winds around 150 mph. The threshold for a Category 5 is 157 mph. Irma made landfall over mainland Florida early Sept. 10 as a Category 4 hurricane. From there, it weakened significantly to a tropical storm Sept. 11 as it powered north toward Georgia and Alabama. At 11 p.m. later that day, it weakened further to a tropical depression, and by Sept. 13, it had dissipated over western Tennessee.
Hurricane Jose was on Irma’s tail, but weakened to a Category 1 storm before stalling out at sea.
When is hurricane season?
The Northern Atlantic hurricane season is June 1 to Nov. 30, but it sharply peaks from late August through September.
What’s the difference between a tropical depression, tropical storm, hurricane, and major hurricane?
The difference between a tropical depression, tropical storm, hurricane, and major hurricane all has to do with wind speed:
- Tropical depression: Wind speed less than 39 mph
- Tropical storm: Wind speed between 39 mph and 73 mph
- Hurricane: Wind speed between 74 mph and 110 mph
- Major hurricane: Wind speed greater than 110 mph
What is a hurricane category, and what do they mean?
A hurricane category, determined by the Saffir–Simpson hurricane wind scale, lets people know how dangerous the hurricane will be:
- Category 1: Very dangerous winds between 74 and 95 mph will cause some damage and power outages for a few days are likely.
- Category 2: Extremely dangerous winds between 96 and 110 mph will cause extensive damage and a near-total power loss that could last up to a few weeks.
- Category 3: Devastating damage will occur from winds between 111 and 129 mph. Electricity and water will be unavailable for up to several weeks, and trees will be snapped or uprooted, blocking roads.
- Category 4: Catastrophic damage will occur from winds between 130 and 156 mph. Even well-built framed homes will lose most of the roof structure and/or some exterior walls. Fallen trees and power poles will likely isolate residential areas, and power outages could last possibly months.
- Category 5: Catastrophic damage will occur from winds 157 mph or higher. A high percentage of homes will be destroyed, and most areas will be uninhabitable for weeks or months.
Why is Hurricane Irma a big deal?
Irma is the fifth-costliest hurricane to hit the mainland United States and caused an estimated $50 billion in damage, according to the National Hurricane Center. At one point, Hurricane Irma was the strongest hurricane the National Hurricane Center has ever recorded in the Atlantic outside of the Caribbean Sea and Gulf of Mexico. It was moving as a Category 5 storm, which means it had sustained wind speeds greater than 157 mph. Category 5 storms cause catastrophic damage when they make landfall. Irma hit the Florida Keys as a Category 4 hurricane and then the mainland as a Category 3.
Hurricane Matthew hit the southern part of Haiti as a Category 4 storm Oct. 4, 2016, and the country still hasn’t fully recovered from that devastating system. Projections had it hitting Haiti hard, but the country was spared from severe devastation.
Where did Hurricane Irma hit?
The storm tracked northwest through the Caribbean, along Florida’s west coast and into Georgia, Alabama, Mississippi, South Carolina, eventually dissipating over Tennessee. Here’s a timeline of Hurricane Irma’s path:
Wednesday, Sept. 6:
- Hit Antigua and Barbuda just before 2 a.m. Half of the 100,000 residents of Antigua and Barbuda have had their homes destroyed or heavily damaged.
- Hit St. Martin, Anguilla, St. Kitts, and Nevis around 8 a.m.
- Hit British Virgin Islands, U.S. Virgin Islands, and Puerto Rico 2 p.m. The governor of Puerto Rico said electricity was restored to 144,000 homes in the days following.
Thursday, Sept. 7:
- Dominican Republic: The storm sustained its Category 5 strength, with maximum sustained winds of 175 mph, but the Dominican Republic avoided a direct hit as it skirted just off its northern coast around 11 a.m. local time.
- Haiti: Haiti was hit but didn’t experience nearly as much impact as expected.
- Turks and Caicos: Irma hit late Thursday and extensive damage is being reported.
Friday, Sept. 8:
- Cuba and the Bahamas: Irma hit as a Category 5 around noon Eastern time.
Saturday and Sunday, Sept. 9 and 10:
- Hurricane Irma pummeled the Florida Keys late Saturday into Sunday as a Category 4 and hit the Florida mainland as a Category 3 storm around 1 p.m. Eastern time Sunday.
Monday, Sept. 11:
- Irma weakened significantly to a tropical storm as it powered north toward Georgia and Alabama.
- The National Hurricane Center says Florida’s coast saw storm surges between 1 and 6 feet, according to the Weather Channel.
- About 11 p.m., Irma weakened further to a tropical depression.
Tuesday, Sept. 12:
- Irma traveled northwest through Georgia and South Carolina on its way to Alabama, Mississippi, and Tennessee.
- As many as 15 million people in Florida are without power, and restoring it could take weeks.
Wednesday, Sept. 13:
When did Hurricane Irma hit Florida?
Hurricane Irma made landfall over the southern Florida mainland around 1 p.m. local time Sunday, Sept. 10 as a Category 3 storm, packing winds of more than 110 miles per hour. It roared its way north, overwhelming the entire state with heavy rains and fierce winds.
How much damage did Hurricane Irma cause?
The damage estimate from Hurricane Irma is up to $100 billion. Hurricane Matthew’s damages last year were about $15 billion. Hurricane Harvey hit the U.S. Aug. 25 as a Category 4 storm, and experts are estimating up to $180 billion in damages. Hurricane Andrew in 1992 killed 55 people and caused more than $20 billion in damage across the U.S. and the Bahamas.
How has World Vision responded?
In the immediate aftermath, World Vision sent semitrucks full of relief supplies to several church partners in Immokalee, Fort Myers, and the Florida Keys. We were able reach more than 18,000 people in some of the hardest-hit areas with food, water, hygiene supplies, and other items. About 400 affected families also received $500 gift cards so they could purchase items they needed most, including materials to repair their homes.
Thanks to generous donors and corporate partners, we were able to keep our warehouses around the country well-stocked to quickly respond to hurricane Irma, Harvey, and Maria simultaneously. Our team was also able to deliver generators to local partners, including churches that needed power to serve hot meals to storm survivors. While the relief phase has moved toward rebuilding, we have committed to providing regular supplies shipments to a church partner in Immokalee to ensure their community is supported through the difficult recovery.
World Vision staff in Haiti and the Dominican Republic also responded to damage in their countries, although they avoided the more severe affects felt in other parts of the Caribbean.
How can I help Hurricane Irma survivors?
You can help World Vision continue responding to disasters like Hurricane Irma around the world.
- Give: Donate to World Vision’s disaster relief fund.
- Pray: Join us in praying for World Vision staff and responders as they help families recover and rebuild: Almighty Father, we ask for Your mercy on those hit hard by Hurricane Irma. In the midst of their struggle to recover, give them patience, peace, and hope that life will get better soon.
Contributors: Chris Huber, Heather Klinger, and Kristy J. O’Hara, World Vision staff